GOST 13047.8-2014

• gost-130478-81.pdf (655.66 KiB)
  ГОСТ 13047.8-81

GOST 13047.8−2014 Nickel. Cobalt. Method for determination of silicon

GOST 13047.8−2014

INTERSTATE STANDARD

NICKEL. COBALT

Method for determination of silicon

Nickel. Cobalt.

Method for determination of silicon

ISS 77.120.40

Date of introduction 2016−01−01

Preface

Goals, basic principles and main procedure of works on interstate standardization have been established in GOST 1.0−92 «interstate standardization system. Basic provisions» and GOST 1.2−2009 «interstate standardization system. Interstate standards, rules and recommendations on interstate standardization. Rules of development, adoption, application, renewal and cancellation"

Data on standard

1 DEVELOPED by interstate technical committees for standardization MTK 501 Nickel and MTC 502 «Cobalt"

2 as AMENDED by the Federal Agency for technical regulation and Metrology (Rosstandart)

3 ACCEPTED by the Interstate Council for standardization, Metrology and certification (Protocol of October 20, 2014 N 71-N)

The adoption voted:

4 by Order of the Federal Agency for technical regulation and Metrology of June 24, 2015 N 816-St inter-state standard GOST 13047.8−2014 introduced as the national standard of the Russian Federation from 1 January 2016.

5 REPLACE GOST 13047.8−2002


Information about the changes to this standard is published in the annual reference index «National standards», and the text changes and amendments — in monthly information index «National standards». In case of revision (replacement) or cancellation of this standard a notification will be published in the monthly information index «National standards». Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet

1 Scope

This standard specifies a spectrophotometric method for determination of silicon (with a mass fraction of silicon from 0,00030% to 0.050%) in the primary Nickel GOST 849 and cobalt GOST 123.

2 Normative references

This standard uses the regulatory references to the following standards:

GOST 83−79 Reagents. Sodium carbonate. Specifications

GOST 123−2008 Cobalt. Specifications

GOST 849−2008 Nickel primary. Specifications

GOST 3118−77 Reagents. Hydrochloric acid. Specifications

GOST 3652−69 Reagents. Citric acid monohydrate and anhydrous. Specifications

GOST 3760−79 Reagents. The aqueous ammonia. Specifications

GOST 3765−78 Reagents. Ammonium molybdate. Specifications

GOST 4204−77 Reagents. Sulphuric acid. Specifications

GOST 4461−77 Reagents. Nitric acid. Specifications

GOST 6006−78 Reagents. Butanol-1. Specifications

GOST 9428−73 Reagents. Silicon (IV) oxide. Specifications

GOST 11125−84 nitric Acid of high purity. Specifications

GOST 3047.1−2014* Nickel. Cobalt. General requirements for methods of analysis
________________
* Probably, the error of the original. Should read: GOST 13047.1−2014. — Note the manufacturer’s database.


GOST 14261−77 hydrochloric Acid of high purity. Specifications

GOST 18300−87 ethyl rectified technical. Specifications

GOST 24147−80 aqueous Ammonia of high purity. Specifications

Note — When using this standard appropriate to test the effect of reference standards in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet or in the annual information index «National standards» published as on January 1 of the current year, and the editions of the monthly information index «National standards» for the current year. If the reference standard is replaced (changed), when using this standard should be guided by replacing (amended) standard. If the reference standard is cancelled without replacement, then the situation in which the given link applies to the extent that does not affect this link.

3 General requirements and safety requirements

General requirements for methods of analysis used by the quality of distilled water and laboratory glassware and safety at work — according to GOST 13047.1.

4 a spectrophotometric method

4.1 Method of analysis

The method is based on measuring light absorption at a wavelength of 610 or 810 nm solution of complex kremneftoristogo compounds, tin dichloride restored, after a preliminary extraction of butyl alcohol from nitric acid medium.

4.2 measuring instruments, auxiliary devices, materials, reagents and solutions

Spectrophotometer measurements in the wavelength range from 590 to 620 nm or from 800 to 820 nm, or photoelectrocolorimeter, which provides measurements in the wavelength range from 590 to 630 nm.

pH meter (ion meter) for measurements in the pH range from 1 to 2.

Nitric acid according to GOST 4461, if necessary, purified by distillation, or according to GOST 11125, diluted 1:1 and 1:2.

Sulfuric acid according to GOST 4204, diluted 1:9.

Hydrochloric acid according to GOST 3118, if necessary, purified by distillation, or according to GOST 14261, diluted 1:1.

Citric acid according to GOST 3652, solution mass concentration of 0.5 g/cm.

The technical rectified ethyl alcohol according to GOST 18300.

Ammonia water according to GOST 3760, if necessary, cleaned, or according to GOST 24147, diluted 1:1.

Filters obestochennye [1]* or other thick filters.
________________
* See Bibliography. — Note the manufacturer’s database.


Ammonium molybdate according to GOST 3765, recrystallized and solution mass concentration of 0.1 g/cm.

The recrystallized ammonium molybdate is prepared as follows: a sample of ammonium molybdate with a mass of 70.0 g were placed in a glass with a capacity of 600 or 1000 cm, pour 400 cmof distilled water, dissolved by heating from 70 °C to 80 °C, filtered through a filter (white or blue ribbon), heated and filtered again. To the hot solution was poured 250 cmof ethyl alcohol, cooled, kept for at least 1 h and filtered off the crystalline precipitate in the porcelain filtering funnel. The precipitate is washed two or three times with ethanol at 20−30 cmand dried in air.

Sodium carbonate according to GOST 83, solution mass concentration of 0.05 g/cm.

Tin dichloride [2], solution of the mass concentration of 0.02 g/cmin hydrochloric acid, diluted 1:1.

Wash solution is prepared as follows: mix 50 cmof sulphuric acid, diluted 1:9, and 3 cmof a solution of molybdate of ammonium.

The 1-butanol (butyl alcohol) according to GOST 6006.

Silicon oxide (IV) GOST 9428.

Sodium silicate 9 water [3].

The silicon solutions of known concentration.

The solution And the mass concentration of the silicon 0,0001 g/cmof sodium silicate is prepared as follows: a suspension of silicate of sodium with a mass 0,5056 g is placed in a platinum Cup or Teflon beaker, dissolve with heating in 20 cmof sodium carbonate solution, cooled, transferred to a volumetric flask with a capacity of 500 cm, adjusted to the mark with distilled water and poured into a plastic container.

The solution And the mass concentration of the silicon 0,0001 g/cmof silicon oxide (IV) is prepared as follows: a portion of the silicon oxide (IV) mass 0,1070 g is placed in a platinum crucible, add 2 g of sodium carbonate, is mixed and fused in a muffle furnace at a temperature of from 1000 °C to 1100 °C for 20−25 min. the Crucible is cooled, the outside rinsed with distilled water, placed in a beaker with a capacity of 250 cm, poured from 80 to 100 cmof distilled water and dissolve the contents of the crucible at a temperature of from 60 °C to 70 °C. the Solution was cooled, transferred to a volumetric flask with a capacity of 500 cm, adjusted to the mark with distilled water and poured into a plastic container.

Solution B mass concentration of the silicon 0,000005 g/cmis prepared as follows: into a measuring flask with a capacity of 100 mtransfer 5 cmof solution A, adjusted to the mark with distilled water and poured into a plastic container.

4.3 Preparation for analysis

4.3.1 To construct the calibration curve in glasses with a capacity of 100 cmstand 0,5; 1,0; 2,0; 4,0 and 6,0 cmof a solution, pour 70 to 80 cmof distilled water and measure the absorption of the calibration solutions in accordance with 4.4.2.

The mass of silicon in the calibration solutions is 0,0000025; 0,0000050; 0,0000100; 0,0000200 and 0,0000300 G.

The light absorption values of the calibration solutions and the respective masses of the silicon to build the calibration graph, given the values of absorption of the calibration solution, is prepared without introducing a solution containing silicon.

4.4 analysis

4.4.1 Sample the sample mass depending on the mass fraction of silicon in accordance with table 1 were placed in a glass or Cup made of quartz glass, glassy carbon or PTFE.

Table 1 Conditions of preparation of sample solution

Weighed sample was dissolved with heating in the amount of 15 to 20 cmof nitric acid, diluted 1:1, boiled for 2−3 min and cooled.

When the mass fraction of silicon of more than 0,003% solution transferred to a volumetric flask with a capacity of 100 cm, adjusted to the mark with distilled water and aliquot part of the solution by volume in accordance with table 1 are transferred into the beakers with a capacity of 100 cm.

To the solution or aliquote part of the flow from 70 to 80 cmof distilled water, set the pH of the solution in the range from 1.5 to 1.7 with ammonia diluted 1:1, or sulfuric acid, diluted 1:9.

The solution was transferred to a separatory funnel with a capacity of 250 cm, poured to a volume of 100 cmof distilled water, 6 cmof a solution of molybdate of ammonium, kept for 10 minutes, pour 2 cmof the citric acid solution, 5 cm.of butyl alcohol and mixed for 30 s. the solution in separating funnel poured 20 cmof nitric acid, diluted 1:2, 15 cmbutyl alcohol and extracted for 1 min. After separation of phases the aqueous phase is decanted into a clean separatory funnel with a capacity of 250 cm, and the organic phase was transferred to a separatory funnel with a capacity of 100 cm, water phase poured 10 cmof butyl alcohol and repeat the extraction. Extraction of 10 cmbutyl alcohol again. After separation of the phases the aqueous phase is discarded and the organic phases combined.

To the combined organic phase poured 50 cmwash solution and stirred, turning the funnel 20 to 25 times. The aqueous phase is discarded and the organic phase was transferred into a dry volumetric flask with a capacity of 50 cm, add two or three drops of solution of tin dichloride and bring to mark with butyl alcohol.

4.4.2 light Absorption of the sample solution measured on a spectrophotometer at a wavelength of 810 or 610 nm or photoelectrocolorimeter in the wavelength range from 590 to 630 nm, using as a comparison solution of butyl alcohol and the cell thickness of the absorbing layer of 3 cm

The value of the light absorption of the sample solution find the mass of silicon for the calibration schedule.

4.5 Processing the analysis results

Mass fraction of silicon in the sample X, %, is calculated by the formula

, (1)

where Mis the mass of silicon in the sample solution, g;

Mis the mass of silicon in the solution in the reference experiment, g;

K — dilution factor of sample solution;

M — weight of sample, g.

4.6 Control of accuracy of analysis results

Control of accuracy of analysis results is carried out according to GOST 13047.1.

The regulations control the precision (limits of repeatability and reproducibility) and the rate control accuracy (expanded uncertainty) of the results of the analysis are shown in table 2.


Table 2 — Requirements of control precision (limits of repeatability and reproducibility) and the rate control accuracy (expanded uncertainty) of the results of the analysis at a confidence probability P=0,95

Percentage

Bibliography